The Marine Corps aircraft was a KC-130T from a Marine Corps Forces Reserve aerial refueling and transport squadron based at Stewart Air National Guard Base in Newburgh, New York, the service said Tuesday. Fifteen Marines and one Navy corpsman died in the crash, the service said.

The flight originated from Marine Corps Air Station Cherry Point, North Carolina, and the squadron was helping to transport personnel and equipment from there to Naval Air Field El Centro in California, the Marine Corps Forces Reserve said in a news release. “Equipment on board included various small arms ammunition and personal weapons. An explosive ordnance disposal team is at the scene as a precaution in the interest of safety,” the release says.

There are reports that a mid-air explosion may have brought the KC-130 military plane down, but local officials could not confirm that.

“At this time, we’re getting more information to work this incident, the scene out, to see further what we need to do,” said Fred Randle, the Leflore County Emergency Management Director.

Secretary of the Interior and Navy SEAL Ryan Zinke and Tennessee Congressman Steve Cohen were among several who tweeted their condolences.

Please join me in praying for or sending good thoughts to the families and unit of the Marines we lost tonight in the C 130 crash #SemperFi